November 25, 2013
Purdue Extension publications help owners care for trees
Mulch under a tree should extend to the edge of the outer branches, called the dripline, to help get water to the root system. (Purdue Department of Forestry and Natural Resources photo/Lindsey Purcell)
WEST LAFAYETTE, Ind. - Homeowners can learn how to best prepare their trees for the harsh winter months and protect them during extended dry periods by following expert advice offered in two new Purdue Extension publications.
Urban forestry specialist Lindsey Purcell said he produced the free publications in response to questions from many tree owners asking how they can protect their trees since extended dry periods the past three summers.
"The past three years have been very challenging for tree survival and trees going into the winter months with water deficits and in decline from the drought will be in jeopardy come the following spring if not cared for properly this fall," Purcell said. "Proper plant health care and good cultural practices such as mulching and watering will make a big difference in survivability."
The three-page publication Winterize Your Trees gives advice on how to help trees get through the cold winter months with sufficient water.
As seasons change, trees prepare to overwinter in the natural state of dormancy, during which they adapt to cold conditions. Trees in urban and suburban landscapes, especially young trees or newly planted, need extra care to ensure a good start in the spring.
"The key to survival is giving trees adequate moisture before winter freezes the world around them," Purcell says in the publication.
Purcell offers the following advice in the publication:
* Wrap trunks of smooth or thin-barked trees in a flexible, white wrap specially made for trees. Such trees - especially maple - are susceptible to sunscald and frost cracks.
* Refresh the mulch so that 2-3 inches of it extend to the edge of the outer branches, called the dripline.
* Fertilize with micronutrients if the trees are not stressed from moisture deficit. Follow label directions.
* Water trees whenever rainfall is insufficient in extended periods, adhering to the recommended amounts in the publication. The best time for watering in the winter is when the temperature is above 40 degrees Fahrenheit.
* Prune trees to remove dying, diseased or dead branches or to improve branching structure. Late fall or early winter are acceptable times.
Drought can have major consequences on tree health and survival. The five-page Drought? Don't forget the trees! explains how homeowners can help drought-stressed trees in the short and long term.
Some of the advice in this publication is similar to that in Winterize Your Trees in that it is crucial to provide sufficient water and to mulch trees to the dripline.
But there are differences, too, including the need to avoid certain maintenance such as pruning and fertilizing.
"Pruning green wood or live branches is not recommended in a drought because trees must expend energy to repair pruning wounds," Purcell said.
He also said fertilizing any tree under stress conditions is not a good practice, especially during drought.
"Trees expend additional energy to process the nitrogen, pulling water from the roots, which can worsen tree health," he said.
Both publications can be downloaded at Purdue Extension's The Education Store. Winterize Your Trees is available at https://mdc.itap.purdue.edu/item.asp?Item_Number=FNR-484-W. Drought? Don’t forget the trees! is at https://mdc.itap.purdue.edu/item.asp?Item_Number=FNR-483-W.
Writer: Keith Robinson, 765-494-2722, firstname.lastname@example.org
Source: Lindsey Purcell, 765-494-3625, email@example.com